Bug: UMS doesn't work for Nuvoton ma35d1f

In this commit, the UMS feature has been enabled. The ums command is available in U-Boot debug mode, but when I try to run the command ums 0 mmc 0, I get the following errors:

MA35D1> ums 0 mmc 0
UMS: LUN 0, dev 0, hwpart 0, sector 0x0, count 0x72c000
g_dnl_register: failed!, error: -19
g_dnl_register failed

I think we are missing the U-Boot device tree setup. To fix this issue, we need to customized the u-boot device tree first.